The invention relates generally to smoothing composite surfaces, such as repaired surfaces.
When a plastic part, such as an automobile panel, is repaired, a material, such as unsaturated polyester resins, primers, fillers, adhesives, or putties, is used to resurface and reshape the damaged areas. The repaired composite material is sanded to obtain a smooth surface. However, sanding creates small imperfections and pinholes in the surface which are visible when a top coat is applied. These pinholes must be sealed before the top coat is applied. The top coat is typically a multilayer coating including a primer, base coat/color, and a clearcoat.
Conventional methods of sealing the pinholes involve several steps and are very time consuming. For example, in one method, a liquid or paste sealer is dispensed onto an applicator, such as a squeegee or a spreader knife. The applicator is then used to wipe the sealer onto the porous surface. This method usually results in an excess film build of the sealer which must be removed before the next step in the process. The excess material is removed by wiping and sanding the residue.
Therefore, there is a need for improved sealers, tools for applying sealers, and methods of repairing pinholes and imperfections in composite materials.